* TSX falls 1.5 percent to 12,300
* Bullion fall to 21 month low hits gold miners hard
* Disappointing U.S. retail sales data cast pall over Canada exporters
By Alastair Sharp
TORONTO, April 12 (Reuters) - Canada's main stock index fell sharply on Friday, with gold miners leading a broad sell-off as the price of bullion plummeted and as contracting U.S. retail sales data signaled flagging momentum in Canada's largest export market.
The index fell well over 1 percent in morning trade, with all ten main sectors in the red.
The country's gold miners, a large contingent on the stock market, were pummelled as the price of bullion broke through key support to hit its lowest level in 21 months.
Barrick Gold Corp was the single biggest weight, down more than 7 percent at C$23.20. The stock has fallen some 20 percent since the start of April.
The Toronto Stock Exchange's S&P/TSX composite index was down 179.25 points, or 1.45 percent, at 12,300.00.
The index is on track to notch a marginal weekly slip, after falling sharply last Wednesday and rising earlier this week.
Gold miners have dragged on the resource-rich index for months, with the sector losing a quarter of its value so far this year as the gold price retreats and investors express concerns about cost overruns.
"The expectations associated with the resource sector in Canada are now extremely low and in turn reflected in share prices," said Bob Gorman, chief portfolio strategist at TD Waterhouse.
"I'm not looking for a massive turnaround here, but the period of dramatic underperformance in the short term is probably coming to an end."
Gorman said U.S. retail sales data showing a second contraction in three months was further proof that tax hikes have stolen momentum from the American economy.
The resulting stretched budgets of ordinary Americans "leads to concerns about economic weakening in general which in turns plays upon the more economically sensitive sectors," he said.
Shares in coal miner Walter Energy Inc, which is locked in a proxy fight with an activist hedge fund, slipped more than 1 percent to C$24.70 as a proxy advisory firm backed the company's board nominees.
Oil company Suncor Energy Inc fell 3 percent to C$28.79. The company, Canada's largest publicly-traded energy company, reported a 225 barrel spill on Thursday and a partner in a North Sea prospect said the company has drilled a dry well.